Relief valve



W. T. BIRCH June 25, 1940.

RELIEF VALVE Filed Jan. 16, 1939 Patented June 25, 1940 vUNITED STATES PATENT OFFICE RELIEF VALVE William T. Birch, Chicago, lll.

Application January 18, 1939, Serial No. 251,230

1Claim.

The present invention relates to relief valves having means for testing the operativeness of relief valves of hot-water heating systems while the valve is subjected to service conditions, to determine whether the valve is available for its intended purpose.

Most of the domestic hot-water heating systems are fed with water from city supply systems, and scale-forming materials and sediment are trapped in the relief valve on the hot side of the l heating system. The scale and sediment accumulate about the valve and its seat as a binding material, binding the valve to the seat and preventing operation of the valve to relieve the heating system when the pressure exceeds a safe value.

Relief valves lfor heating systems have heretofore been provided with levers pivoted about the upper end of the cap of the valve for hand manipulation to relieve the spring pressure on the valve so that the system pressure may lift the valve, or have been connected with the valve through linkage means to lift the valve. Valve lifting arrangements which include such lever means add appreciably to the manufacturing and maintenance costs, and when they become worn they become difiicult to manipulate.

Levers projecting from the upper end of the cap are attractive to young persons, and encourage unauthorized manipulation in a manner likely to result in leaky valves.

It is an object of this invention to provide a relief valve with simple means to positively push the valve from its seat, and while the valve is subjected to the system pressure.

It is a further object of this innventionto provide means insertable in the discharge outlet of a relief valve, and adjustable therein to push the Valve from its seat while providing for the discharge of water through the outlet to wash the seat.

It is a further object of this invention to provide means insertable in the outlet of a relief valve to push the valve of! its seat and effectively seal the outlet against discharge of water, so that a cap such as that described in the William T. Birch Patent 2,067,229, issued January 12, 1937, may be removed to facilitate repair and renewal of parts located therein. a

Other and further objects and features of this invention will be apparent fromthe disclosures in the specification and the accompanying drawing.

In the drawing:

Figure 1 is a vertical sectional view of a relief valve equipped with the valve pushing means of the present invention, and with parts broken and with parts in plan;

Figure 2 is a vertical. sectional view of the relief valve of Figure 1, with parts broken and with parts in plan, and showing a modification of the discharge outlet.

Means for positively pushing the valve disk of the valve from its seat is described hereinafter, and, for the purpose of illustrating the application of such valve pushing means to a relief valve, the applicant has shown in his drawing a relief valve similar to that shown and described in his Patent No. 2,067,229, issued to him on January 12, 1937. It will be understood'that the relief valve is shown for purposes of illustration, and not by way of limitation, for the valve-lifting means of the present invention are obviously applicable to relief valves other than that shown.

As shown in Figure l, the relief valve has a casing indicated generally at I0. At one end, the casing 'is provided with a cold water inlet il, which is normally closed against flow of hot water from the heating system by a check valve I2. The other end of the casing is provided with an outlet i3 for connection to a hot-water heating system, and in fluid communication with an outlet chamber I4 in the casing.

The outlet chamber is closed on one side by a diaphragm I5, formed of a pair of dished members, and the diaphragm I5 is seated at its peripheral portion on the casing I0, and is held in place by a hood I6 threaded in the casing.

An inverted cup-shaped member I1 is provided with an extending reduced portion which extends through a central aperture inthe diaphragm I5, and the diaphragm is clamped between the member l1 and a nut I8 threaded on the upper end of the reduced portion.

A hexagonal plug I8 has an upwardly extending reduced portion threaded into the reduced portion of the member l1, and a primary valve 20 is entered into a recess formed in the lower end of the plug. The valve 20 normally engages a valve seat member 2| threaded into a bore 22 of the casing I0, and the member 2| is provided with a central bore 23 forming a port for the discharge of uid when the valve 20 lifts as the diaphragm is flexed upwardly by an excessive pressure in the heating system. 'I'he bore 22 is large enough to permit the withdrawal therethrough of the plug I! for renewal or'inspection of the valve 20.

The lower edge of the annularwall of the member i1 is recessed. and a secondary annular valve 24 is entered into the recess to cooperate with an aligned and annular boss 2l, formed on the casing I8, to close the port 23 in the event that the primary valve 28 or the'member 2| are withdrawn, or that the valve 28 becomes badly worn.

The valve seat member 2| extends inwardly into the chamber Il so that its inner end provides a seat disposed in a plane above that of the seat provided by the boss 25, and so that the secondary valve 24 is held in spaced relation to its seat when the primary valve is in good condition.

The hood I6 is open at its upper end and is provided with a cap 28 which is threaded thereon. An adjusting screw 21 is threaded into the cap to bear against the central portion ot a pressure plate 28 and compress a coiled spring 28 to exert pressure on the diaphragm I5.

The pressure plate is reduced in section at its central portion to provide a central recess, and the lower end of the screw is reduced to llt in this recess and provide a shoulder adapted to engage the upper face of the pressure plate should the reduced end of the screw be forced through the plate when an attempt is made to set the relief valve for an unauthorized and excessive pressure.

Near its lower end the member 2| is enlarged at 30 to provide a shoulder adapted to abut the casing and limit inward travel of the member 2|, and the lower face 3| of the enlarged portion is machined accurately to provide a seat for cooperation with an engaging member described hereinaiter.

The lower portion of the bore 22 is enlarged at 32, and is threaded.

A valve lifting means comprises a tubular member 33 which is exteriorly threaded at its upper end at 34, interiorly threaded at its lower end at 35, and provided with a flange 36 at its lower end.

'Ihe upper edge of the tube is accurately ground, as indicated at 31, so that when the member 33 is entered into the enlarged portion 32 of the bore 22 of the casing I0, the edge or face 31 will form a fluid tight joint when it engages the machined face 3| of the member 2|.

A pin 38 is secured to the tubular member 33 and extends outwardly thereof, and is centrally disposed in the bore oi the member and supported by a tripod 33. v

In Figure l, the member 33 is shown threaded into the bore 22 with the edge 31 in sealing engagement with the lower face or seat 3| of the member 2|, and with the pin 38 extending centrally through the bore of the member 2| and into the chamber Il to engage the lower face of the valve 28 and push it off its seat so that water in the chamber Il may be discharged past the pin and through the member 33.

'I'he pin 38 necessarily restricts the bore of the member 2| somewhat and causes the water being discharged to acquire a velocity head, with swirling and turbulence about the seat of the valve 20 tending to scour the seat of the accumulated sediment. 'I'he pin 38 may be suitably shaped to augment this swirling of the discharged water.

It is usually desirable that the tubular member 33 be provided with a discharge pipe extension 43 threaded into the internally threaded bore 3l to carry the water in some convenient direction.

When the member 33 is provided with the pipe extension 43, the pipe will usually ailord enough hand-grip surface so that one may readily turn the member 33 by hand to cause it to move upwardly in the bore 22 and result in the unseating o! the valve by the pin 38. 'Ihe flange 33 may have a roughened surface so that the member 33 may be turned by a grown person without the use of tools, but, in general. it is desirable that the ilange be or irregular outline to suggest to young persons lack of adjustability without the use of tools, and so discourage unauthorized movement of the member 33.

As shown in Figure 2, the pipe extension 48 may be replaced by a plug 4|, so that the bore 22 is sealed against water flow when the member 33 is used to unseat the valve 20, because the face or edge 31 is now in sealing engagement with the seat 3|.

When the bore 22 is effectively sealed by the two sealing means just described, the cap 28 may be removed, as shown in Figure 2, so that the pressure plate 28 may be removed. It is obvious that the whole operation of sealing the discharge outlet, removing the cap, replacing the pressure plate, restoring the cap, and removing the sealing means, is a task of only a few minutes' duration, and can be performed while the heating `system is functioning.

The pin 38 and its tripod amount to an apertured extension of the tubular member 33. and it is obvious that the pin may be variously supported, and that other apertured extension means may be substituted for the pin and tripod assembly to lift the valve.

I am aware that many changes may be made and numerous details of construction varied through a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

A relief valve for hot water heating systems, said valve comprising a casing having a compound diaphragm therein dividing the casing into a water chamber and a bonnet chamber, a compression spring in said bonnet chamber and engaging said diaphragm, a removable cap on said bonnet carrying spring pressure adjusting means engaging said spring, means in said casing de- 'flning a threaded discharge outlet communicating with the water chamber, a ported valve seat member threaded into said outlet and presenting a valve seat in the water chamber, a valve disk secured to said diaphragm and urged thereby into engagement with said seat, means whereby said cap may be temporarily removed and said spring released for adjustment of said compression spring while the relief valve is operating under normal pressure condition, said means consisting of a tubular member threaded into said bore and having an upstanding linger enterable into the water chamber to lift said valve and said diaphragm, and a plug threaded into said member. WILLIAM T. BIRCH. 

